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Evaluation and application of ultra-low-frequency pressure reactivity index in pediatric traumatic brain injury
Paolo Gritti1, Marco Bonfanti2, Rosalia Zangari2
1Department of Anesthesia and Critical Care Medicine, Papa Giovanni XXIII Hospital, Bergamo, Italy. grittip@libero.it.
Insights
An ultra-low-frequency pressure reactivity index (UL-PRx) can predict outcomes in pediatric traumatic brain injury (pTBI) patients. This method offers prognostic insights for pTBI management in intensive care units.
Area of Science:
- Neurology
- Pediatric Critical Care
- Neurocritical Care
Background:
- Cerebral autoregulation (CA) status is vital for managing traumatic brain injury (TBI) patients.
- Evidence on CA in pediatric TBI (pTBI) is limited.
- The pressure reactivity index (PRx) estimates CA but requires high-resolution data.
Purpose of the Study:
- To evaluate an ultra-low-frequency PRx (UL-PRx) using lower-resolution data.
- To assess UL-PRx association with 6-month mortality and outcomes in pTBI.
- To determine the prognostic utility of UL-PRx in pediatric neurocritical care.
Main Methods:
- Retrospective collection of data from pTBI patients (0-18 years) requiring intracranial pressure (ICP) monitoring.
- Processing of data using an in-house algorithm in MATLAB.
- Calculation of UL-PRx based on data sampled at approximately 5-minute intervals.
Main Results:
- UL-PRx showed significant association with 6-month mortality and unfavorable outcomes in 47 pTBI patients.
- A UL-PRx threshold of 0.30 effectively discriminated between survival and mortality (AUC: 0.90) and favorable vs. unfavorable outcomes (AUC: 0.70).
- Mean UL-PRx remained a significant predictor of outcomes, even after adjustment for IMPACT-Core variables.
Conclusions:
- UL-PRx is a valuable tool for assessing CA in pTBI patients.
- UL-PRx has potential prognostic and therapeutic implications for pTBI management.
- This method may be beneficial in pediatric intensive care units for evaluating CA status.
Purpose:
While clinical practice suggests that knowing the cerebral autoregulation (CA) status of traumatic brain injury (TBI) patients is crucial in assessing the best treatment, evidence in pediatric TBI (pTBI) is limited. The pressure reactivity index (PRx) is a surrogate method for the continuous estimation of CA in adults; however, calculations require continuous, high-resolution monitoring data. We evaluate an ultra-low-frequency pressure reactivity index (UL-PRx), based on data sampled at ∼5-min periods, and test its association with 6-month mortality and unfavorable outcome in a cohort of pTBI patients.
Methods:
Data derived from pTBI patients (0-18 years) requiring intracranial pressure (ICP) monitoring were retrospectively collected and processed in MATLAB using an in-house algorithm.
Results:
Data on 47 pTBI patients were included. UL-PRx mean values, ICP, cerebral perfusion pressure (CPP), and derived indices showed significant association with 6-month mortality and unfavorable outcome. A value of UL-PRx of 0.30 was identified as the threshold to better discriminate both surviving vs deceased patients (AUC: 0.90), and favorable vs unfavorable outcomes (AUC: 0.70) at 6 months. At multivariate analysis, mean UL-PRx and % time with ICP > 20 mmHg, remained significantly associated with 6-month mortality and unfavorable outcome, even when adjusted for International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT)-Core variables. In six patients undergoing secondary decompressive craniectomy, no significant changes in UL-PRx were found after surgery.
Conclusions:
UL-PRx is associated with a 6-month outcome even if adjusted for IMPACT-Core. Its application in pediatric intensive care unit could be useful to evaluate CA and offer possible prognostic and therapeutic implications in pTBI patients.
Clinicaltrials:
GOV: NCT05043545, September 14, 2021, retrospectively registered.
